Method and apparatus for producing elastic strip material



J. R. GAMMETER METHOD AND APPARATUS FOR PRODUCING ELASTIC STRIP MATERIAL March l 1927.

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J. R. GAMMETER METHOD AND APMRATUS FOR PRODUGING ELAsTIc STRIP MATERIAL Filed Maron 14, 1924 5 Sheets-Sheet 2 7 7| .7 ,900 i 0V WM as IL 8/ P f m .w a0 n I .M 7 4. d Q .0.. ...M w. 5 ..5 6 M l v\4 llhlllln! 1. a o ilMH-'Ilnvll l 2 6 n 0d 6 0.1. U. zu. f a/. w fw 5 ...uw u M f. @u M 416%201 -L 6665 M uw .TQM

March 1 1927.

J. R. GAMME-ren METHOD AND APPARATUS FOR PRODUCING ELASTIC STRIP MATERIAL Filed March 14, 1924 3 Sheets-Sheet 5 Jiffy Patented Ms 151927.

UNITED sTA'rEs PATENT oF JOHN n'. GAMMETER, oF'AxnoN, oHIo, Assreron To THE n.

1,619,342 Fica.

0F EW YOBK, N. Y., A CQBPORATION OF YORK.

METHOD AND APPARATUS ronrnontrcmu nLAsTIc STRIP MATERIAL.'-

Ap-plic'ation led March 14, 1,924. Serial No. 699,231.

. ber. The particular l"embodiment of my invention which is shown in the accompan drawings" 'and described herein is especiall adapted for braiding a covering of threads onto a rubber. core structure whlle the-'latter vis in a stretched, attenuated conditi-on, so

that the braided covering will l-i" ""t the contraction of the` resulting structure when the all tensioning means itself.

same-is released from other than the covering A structure of this character isof especial value, for example, as a cushion element or shock-absorber for the landing gear of an aeroplanewherein it may be used to provide ying a cushioning element of appropriate' elasticresistance without requiring such weight of rubber as would be necessary tol provide the rubber we re free to elongate' and contract throughout its natu ral range. The braided covering is alsoA 1 adapted tolimit the elongation and .contrac- -tion of-the strip to a certain,'definite range. Heretofore, so far as I am aware, m` ro,-

ducingsuch structure by' feeding Ja ru bert core under tension through a braiding machine or the like, the core has been progressively tensioned by means of a friction brake mechanism, as by braking 'a vstock reel from which thecore is drawn through the braider, with the result of lack ofuniformity in the 'characteristics of the-product due to the variable and indeterminate action of the brake orV 40 y elastlc of the reel in giving oii the core material.

My chief object is to provide an improved nous` strip. Another object is to provide apparatus-readily adaptable for producing such structures of different cross-sectional sizes and of different ranges of Vstretchability. be

Of the accompanying drawings, Fig. 1 is a front elevation of apparatus v cmbodyingand' adapted to carry out my incord structure or the like, of the accurate proce'- dure and apparatus for producing the same, and especially for producing it as a contin velrton in its therein.

Fig. 2 is a'front elevation of parts of the same, on a larger scale, parts A being broken away and ,in` section.

Fig. 3 is a side elevationv of the apparatus as viewed from the right of Fig. 1.

.Figgv 4 is'a horizontal section on line 1v-4 of Fig. 2.- ,f

Fig. 5 is a perspective,- fragmentary view preferred form, and the work Goonacn comm;

sol

of the product, part of the cover being removed' forthe vpurpose of illustration. v.

General description.

'Referring to the drawings, and first L'more particularly to Fig. 1, vvthe apparatus comprises two braiders. A and B, which may be of known design, for braiding respectively an inner and an outersheath of threads upon the rubber core structure, a large -feederpulley C at the upper part of the machine for pulling the` work upward through said braid,- ers,A al retarding devicel D adaptedio'ect a stretching of the core material as the latter passes to said braiders, change-speed gearing E for varying therelative speeds of said feeding4 pulley and the rollers of said retarding device, and 'a frictionally driven reeling device "F for the finished work, the

core structure, and to reel up the finished y product, lesignated 13'.

I Braz'dcr /ive mechanism.

The braiding mechanism, of the usual doubledeckl type for braiding two coversor sheathsupon strip material, comprises a 'pair of sideframes 14, 14, upon which are mounted the several parts of the braiding mechanism, including the feeder pulley 25, said frames being mounted upon a. table motor 16 (Fig. 1.), here shown as secured to an overhead support, saidmotor having 1t connection to a countershaft 17, and the latter having belt connection "to-a pulle 20 vmounted on a stub shaft 21 projecting rom one ofthe frame members 14. Said pulley The' driving mechanism comprises a 1'06.

apparatus being adapted continuously to 85 `with to pull the latter throu is provided on itsrear face with a bevel gear 22 adapted to drive the braiders in a well known manner, the driving mechanism of the two braiders being connected by a vertical, drive-shaft 27.

i Feedert pulley,

The upper end of the shaft 27 is provided a worm 28, meshed with a worm gear secured to one end of a shaft 36, journaled in the respective side frames 14, (see especially Fig. 3), he other'end of said shaft being provided with a gear 37 which is mesher` with a gear 38 secured to the adjacent end of a parallel shaft 39, the latter being jour- 'naled in suitable brackets mounted on the respective frame members 14. A pinion 40 loosely journaled on said shaft 39 near its middle is mashed with a gear 41 formed on the periphery of the feeder pulley 42, said feeder pulley being secured on a shaft 43 journaled in the to s of the frame members 14. The feeder pu ley 42 is formed on periphery with laterally tapered groove face adapted to receive the finished work 13 in a lurality of spiral turns, so that the pulley has sufficient frictional contact with the work h the machine under substantial tension, an to permitthe elastic work to slip laterally towarda flange at the small end of the said face, while it grips the pulley against circumferential slippage, .so as to maintain alilgnment of the work as it passes from the raiders to the feeder pulley notwithstanding the spiral disposition of the work on the pulley.

The pinion 4() has its hub formed with clutch teeth adapted normally to be engaged a complemental clutch member 44 slidb. ably keyed upon its shaft 39, said clutch being provided with a shipper-lever 45 pivoted on a collar 46 loosely mounted upon the shaft 43, between spacing collars 47, 47, secured on said shaft. The flexible, free end of said Shipper lever overlies a hereinafter described bracket 80, secured to the frame members 14, and said lever is provided with a stud 45, adapted to be inserted in one or the other of a pair of apertures 80, in said bracket, to hold the, clutch engaged or disengaged. The front end of the shaft 39 is provi ed with a pulley 48 having driving connection, through drive-belt 49, with a counter-shaft 50 journaled in overhead brackets (see Fig. 1), for driving the reeling device F..

- For manually driving the feeder-pulley 42 on occasion, as when threading the work through the machine in preparing'for operation, with the clutch 44 disengaged, a shaft 51 has secured thereon a pinion `52meshed i 4 with the gear 41 of the feeder pulley, said shaft 51 being journaled in the legs of a U-shaped bracket 53, shown most clearly in Fig. 2, extending from the frame members pawl 56 pivoted on the bracket 53, to prevent y unintended recession of vthe feeder pulley '42 under the tension of the work. A pair of parallel guide fingers 57, 57 mounted on the bracket 53, are adapted to guide the finished work 13 as it passes from the feeder pulley 42 to the reeling device F.

Core tensioning device.`

The core tensioning device comprisesan upper set of elongated rollers 58, 58, journal-ed on a bracket 60 secured under the table 15, and a lower set of rollers 59, 59, journaled upon a similar bracket 61, the `rollers of each set being positioned in staggered relation to those of the other set, to provide maximum contact of the rollers withrthe rubber strands 10 adapted to constitute the core, said strands being threaded about rollers of the two sets alternately. Secured to the hubs of the rollers 58, 59 are sprocket-s 62, 62, 63, 63, respectively, and a sprocket chain 163 is mounted upon said sprockets alternately, in parallel with the work, said" chain also passing about flanged guide sheaves 64, 65, secured to the table 15, and a slow-speed drive or hold-back sprocket 97 hereinafter described, constituting a part of the change-speed gearing E, for compelling the core tensioning rollers 58, 59 to rotate at a determinately slow peripheral speed with relation to that of the feeder pulley C.'

Interposed operatively between the core tensioning rollers 58, 59 and the braiders is a device for maintaining a substantially constant determinate tcnsioningforce upon the core strands as they pass to the braiders, said device comprising a flanged roller 66 journaled in the free end lof a vertically swinging frame 67, the latter being pivoted at 68 to the table 15. A flexible cable or chain 69 has`4 one of its ends secured to the free end of the frame 67, passes around a pulley 70 mounted below said frame, thence around pulleys 71, 72 mounted above said frame, and has its other end provided with a depending setof weights 73, 73, adapted to exert a downward pull upon the roller .66 journaled in said frame, said roller being urged upward against its own gravity and that of the frame 67 and the weights 73 by loops of the strands l10 passing partly around said roller between the tensioning rollers 58, 59 and the braiders, the yweights 7 3 being adapted to be varied in number in acofthe tensioning rollers 58, 59 and the feedv pulley C, whereby the core strands may be fed froma source of supply ata suitable l mg force of the floating roller. 66

rate to maintain the frame 67 in ,substantially horizontal position, so that the loadwill be ke t substantially constant. a

or guiding the .strands into close association with each other as they pass to the braiders, the table tral aperture 74 in which is mounted a guide from,

sleeve 75 for said strands, said sleeve being' formed with a circular aperture and a flared conical guide extending downwardly thereso as to guldejthe strands into acompact bundle. v

- Ullangefspeed giemz'ng.

` 82, with a sprocket 83 secured on the main drive-shaft` 84 of thechange-speed gearing E. A forked gear-shifting lever 85, fulcrumed upon the shaft 84, straddles a gea-r 86 slidably keyed on said shaft, so that said lever and gear are manually adjustable longitudinally on said shaft. One end of the lever- 85 is provided with a h andle 87 and a spring-bolt '187 adapted to be" engaged selectively in one or another of an inclined series of apertures 88 formed in a `locking-plate 89, (see Fig. 3) to hold angular position for a gear 90, journaled in its forked end and meshed with the gear 86, to be engaged selectively with one or another of a series of graduated gears 91 91, secured upon an adjacent shaft 92.

Said shaft 92 is provided at its front end with a gear 93 (Fig. 1) meshed with an idler gcar.94, the latter being journaled on an adjustable spindle mounted in an arcuate slot 94a in the front frame of the change-speed device, said gear 94 in turn being meshed with a gear 95 on the front end of a countershaft 96, uponthe rear end of which is se- 95 to 'be of optional size,

lor threa cured the sprocket `97,1abovereferred to, for maint' ining the relatively slow speed of the tensioning rollers 58,I 59. The adjustable feat-ure of the idler gear94 permits the gear o thus multiplying the number of speed ratios available in the device. Thefront end of the shaft 92 also is providedwith a handwheel 98 for.. preparatoryfhand peration or for preserving' the tension of the core materia-l while the lever 87 is reset to change the` gear ratio..

@are arterial supply.

A reel 99 (Fig, 1) is journaled on a floor bracket 100 adjacent the braiding apparatus and ada ted to give off the rubber strands gs 10 under very -little tension, said strands preferably' being initially dusted with: suit-able lubricant such as soapstone,

-15 is formed with a cen,

l.-i'na'chlne and being j ourna said lever 85 in suitable and .Wound preferably with uniform but little tension, upon said reel, the respective ends of saidvstrands' being grouped together and tied, and each end provided with an elastic leader, the leader at the forward end of the set of strands facilitating the starting ofthe Work through the braiding permitting the leading end portion of the core to be braided while under suitable tension, and the leader at the' rear end of the set of strands serving the same purpose vvvith relation end portion of the core. The hub of the reel 99 is provided with a brake-drum 101, engaged by a lightly Weighted brake-band 102, for insuring the uniform withdrawal of the Work Without subjecting` the latter to very much tension.

Take-up reel. y'

For Winding up the finished work, 13, a reel 103 (Fi/g. 1) is journaled on a pair of floor brackets 104, said reel being secured upon a common shaft with a gear 105, the... v latter being meshed with a drive pinion 10'6 secured on a rojecting shaft 107, the latter 12d in a pair of Hoor brackets such as 108 (Fig. l) at one side of the brackets 104. 'The shaft 107 is adapted to be frictionally driven by a pulley 109,`suitable frictional connection being operatively interposed between said shaft and said pulley, the latter bein connected by a driving belt 110 with a puey 111 on the counter shaft 50 hereinbefore'described.

For guiding the Work evenly onto the reel 103, a guide-sheave 112 is journaled on an arm 113, the latter being mounted on a return screw shaft 114, and slidably secured againstv rotation, for moving the guide- `sheave back and forth axially of the reels 103. For driving the shaft 114, said shaft is provided With a ratchet. 115 secured tl1ereon and adapted to be driven by a pawl 116 mounted on a paWl arm 216 pivoted on the shaft`114 and adapted to be oscillated by a pitman 117 V'connecting said pawl arm with an eccentric 1118 on the shaft-107.

Operation.

'or tensioned with a determinate force, as

dsiredf, a .two-ply cover is braided upon the tensioned core, and the resulting structure is Wound onto the reel 103, all of these operations being performed by the machine automatically, except that the relative speeds of the feed pulley and the tensioning rollers, or the force of the weights 73, is varied fromtime to time by the operator to maintain the desired correlation. For producing a strip" having a core stretched to, a uniform tension throughout, the preferred practice is to use such weights as to provide a given tension upon the core, and then vary the speed of the hold back means as may be necessary to prevent the floating roller 66 from excessively rising or falling.

lVhen the rollers 58, 59 are all adapted to be driven at the same surface speed, as shown, there may be `a slippage of the core strands on those of the rollers which aie nearest to `the floating roller 66, dependingr upon the loading of the latter. I do not find this objectionablebut my invention is not wholly limited to driving said rollers at the same surface speed. The arrangement of said rollers is such that, by guiding the strands in a sinuous path and thereby maintaining an extensive frictional contact therewith, sli page of the strands on the rollers nearest t e supply reel at least is prevented, so that the strands may be fed 'from the reel at a determinate speed and with such little tension therein as to malte the linear rate of feed a dependable measure for so supplying the strands as to give them a determinate tension in tlie finished Jroduct. As this arrangement of the holdack vrollers is adapt- 'ed to provide a determinate rate of feed of the substantially yuntensioned rubber, a substantially uniform percentage of stretch may thereby be obtained, and 'I do not wholly limit my .claims to the loading of the strands as they pass to the braiders.

Modifications may be resorted to without departing from the sco e of my invention, which is not limited, or example, to the round-sectioned product here shown,Y and I do not wholly limit my claims to the specific construction shown or the exact procedure described. A f I claim:

l. Apparatus of the character described comprising means for progressively fabricating a iexible,`extensible fibrous structure in association with strip rubber, means for supporting a supply of the strip rubber, means for pulling the product continuously from the fabricating means, hold-back means other than the supply-supportin means for re- -tarding the movement of the rubber to the fabricating means, and means for compelling the withdrawing means and the hold-back means to function with a constant, determinate ratio of feeding speed.

2. Apparatus of the character described comprising means for fabricating a flexible, extensible fibrous structure in association with strip rubber, means for pulling the product continuously from the fabricating means, hold-back means for i'etai'ding the movement of the rubber to the'fabricating means, means for compelling the pulling tensible, fabricated p structure associated therewith, said apparatus comprising means for progressively fabricating said structure in association with said strip rubber, means for continuously pulling the product fromsaid fabricating means, liold-back means adapted to give off said strip rubber to said fabricating means, and drive mechanism operatively connecting said hold-back means and said pulling means.

for producing elastic stripA 4:. Apparatus material comprising strip rubber and an extensible, fabricated structure associated therewith, said apparatus comprising means for progressively fabricating said structure in association with said strip rubber, means for continuously mlling the product from said fabricating means, and hold-back means adapted to give off fabricating means, the said hold-back means comprising a series of rollers so relatively positioned as to guide the strip rubber in a sinuous path.

5. Apparatus for producing elastic strip material lcomprising strip rubber and an eX- tensible fabricated structure associatedtherewith, said apparatus comprising means for progressively fabricating said structure in association with said strip rubber, means for continuously pulling the product from said fabricating means, hold-back means adapted to give off said strip rubber to said fabricating means,l and means for exerting a determinate, uniform tension upon said strip rubber as it passes from said hold-back means to said fabricating means, said holdback meanscomprising a series of rollers so relatively positioned as to guide said strip rubber ina. sinuous path.

6. Apparatus for producing elastic strip material comprising strip rubber and an extensible, fabricated structure associated therewith, said apparatus comprising means for progressively fabricating said structure iii association with said strip rubber, means for continuously pulling said strip rubber from said fabricating means, hold-back means adapted to give off said strip rubber to said fabricating means, means for exerting a determinate, uniform tension upon said strip rubber as it passes from said hold-back means to said fabricating means, said holdback means comprising a series of rollers so relatively positioned as to guide said strip said strip rubber to said ico i ifs rubber in "a sinuous path, and said tension means comprising a floating roller adapted to ride in a loop of said strip rubber, and weighting means for said floating roller.

7. Apparatus for producing elastic strip material comprising strip rubber and an extensible, fabricated structure associated therewith, said apparatus comprising means for progressively lfabricating said structure in association with said strip rubber, means for continuously pulling said strip rubber from said fabricating means, hold-back means adapted to give off said strip rubber to said fabricating means, av floating roller adapted to ride in a loopof said strip rubber4 between said hold-back means and said fabricating means', and drive mechanism operatively connecting said hold-back means and said pulling means.

8. Apparatus for producing elastic strip material comprising striprubber and an extensible, fabricated structure associated therewith, said apparatus comprising means for progressively fabricating said structure in association with said strip rubber, means for continuously pulling said strip rubber from said fabricating means, hold-back means adapted to give oil said rubber to said fabricating means, a oating roller adapted -to ride in a loop of said strip rubber between pulling. means, said drive mechanism being adapted for change of speed ratio and said floating roller being provided with means fordeterminately varying its force upon the work.

9. Apparatus for producing elastic strip material comprising strip rubber and an extensible, fabricated structure associated therewith, said apparatus comprising means for progressively fabricating said structure in association with said strip rubber, means for 'continuously pulling said strip rubber from said fabricating means, hold-back means adapted togive off said strip rubber to said fabricating means, and drive mechanism operatively connecting said hold-back means and said pulling means, said hold` back means comprising a series of rollers so relatively positioned as to guide said strip rubber in a sinuous path.

In witness whereof I have hereunto set my hand this 11th day of March, 1924.

' JOHN R. GAMMETER. 

